Hi,
One of my X-10 Powermid transmitters spontaneously goes into transmit mode (the LED is permanently lit) and swamps other devices around the X-10 Receiver, making it impossible to send IR commands.

I have a few X-10 Powermid transmitters in different rooms and a Powermid receiver at my TV/video/Hi-Fi setup. For reasons I can't establish (and X-10 seem unable to help with) one of my transmitters will spontaneously go into transmit mode,and its red indicator LED stays on permanently. When I'm using my IR remotes in that room I can usually override this LED "stickiness" by using my TV/video remotes. Rubbing my finger on the plastic exterior of the Powermid X-10 will usually turn the LED off too!

However if this transmitter goes into "always on" mode I can't use my X-10 transmitters in my other rooms, since the rogue "always on" transmitter swamps the receiver and by extension the other devices near the receiver.

I've tried moving the problem transmitter to different locations but it always turns itself to LED-on mode within a short while. I've tried swapping it with my other transmitters but the problem remains.

Does anyone have any idea of the cause and maybe a solution? BTW I'm in Dublin, Ireland which is a 230v/50hz AC area.
Thanks

I'm not sure what you mean. Does the same transmitter do this no matter what room it's in or does any transmitter in this location exhibit the problem?

I had the same problem and had to replace the unit - sorry I can't be more help.

I've never had that problem with mine (I use several) but I have heard that they are really sensitive to stray light from aquarium lights, sun, etc. Any light source that may contain IR (or close). All you can do is change placement if that's the problem.

I had the same problem with different transmitters in the same location. So extraneous source of IR light or, as far as I can establish, of RF interference. And, as I said, the action of rubbing the exterior plastic of the Powermid will turn off the LED.

I was hoping for some tweak to the circuit that would make it less sensitive to whatever is triggering the TX mode.

Thanks for all the contributions.

Regards,

Roy

The Powermids are ultra-sensitive to sunlight and maybe to fluorescent lights.

The IR receiver is a self-contained module. There are no adjustments that can be made to it.

There's an excellent whitepaper on IR interference sources at...

   [Link: vishay.com]

I have used the X-10 Powermid a couple of years ago (ST539 – RE549). It did work fine for a couple of weeks and then developed the same problem . I have found that the problem douse not starts immediately after power on but after about an hour. I have removed the top of the pyramid and the problem was solved. The transformer inside this transmitter is heating up the unit until it fails. Try removing the top (4 screws in the bottom of the unit under the rubber) and operate it like this for a wile to see if this solves your problem, drilling air vent holes might solve your problem.

Wow, you realize that this thread is over TEN YEARS OLD?

Had the same problem, only in the winter when tree leaves were no longer shading the house and the morning when the sun was low in the sky. The solution was to use a cardboard shield to prevent direct sunlight from reaching the transmitter.